JPH10325629A - Leaf spring for reciprocation type refrigerator, manufacture thereof, and reciprocation type refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cause the characteristics of a leaf spring to approximately coincide with a calculating result and to reduce the occurrence of unevenness in the characteristics of each of leaf springs, in a treated part where the unnecessary part is removed by heat. SOLUTION: After a slip hole 31a of each leaf spring 31 is formed by a treated part wherein an unnecessary part is removed by laser treatment, a thermally influenced part being at a boundary with the unnecessary part of the treated part, namely, the two end parts in the direction of width of the slit hole 31a are polished for removal. In this case, a part wherein material characteristics are changed by the heat of laser is completely removed. As noted above, by polishing the thermally influenced part for removal, the part wherein the material characteristics are changed are removed, the material characteristics of each leaf spring 31 are approximately uniformized at any part, and the characteristics, such as the spring constant of each leaf spring and rigidity, are caused to approximately coincide with a result calculated by estimating an amount to be prepolished for removal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leaf spring for a reciprocating refrigerating machine which elastically supports a movable body for compressing or expanding gas in a compressor or expander so as to reciprocate, a method of manufacturing the same, and a reciprocating refrigerating machine. Machine belongs to the technical field.

[0002]

2. Description of the Related Art Generally, a reciprocating refrigerating machine of this type includes an expander for generating cryogenic-level cold by reciprocating a displacer, and a compressor for compressing a refrigerant supplied to the expander. Stirling refrigerators and the like are well known. This Stirling refrigerator is configured such that a displacer that defines an expansion chamber in a cylinder of the expander and a piston that defines a compression chamber in a cylinder of the compressor reciprocate in each cylinder. Then, in this refrigerator, when the displacer or the piston reciprocates, it is required that vibration in the direction perpendicular to the reciprocation direction of the displacer or the piston is reduced as much as possible in order to reduce the vibration.

[0003] Therefore, conventionally, for example, Japanese Patent Application Laid-Open No. 5-2884.
As disclosed in Japanese Patent Application Publication No. 19, a leaf spring that elastically supports a piston in a compressor so that the piston can reciprocate in its axial direction and cannot move in a direction perpendicular to the reciprocating direction of the piston (piston radial direction). It is known to reduce the vibration of its piston by use. In other words, since this leaf spring has high rigidity in the radial direction of the piston and hardly deforms in that direction, the vibration of the piston is reduced by reducing the radial deflection of the piston, while the elastic deformation is large in the axial direction of the piston. Therefore, the entire movable body including the piston is elastically supported so as to reciprocate in the axial direction of the piston. Also, in the expander, similarly to the compressor, the displacer is elastically supported by using a leaf spring.

The leaf spring usually has a spiral slit or the like extending between the central portion and the outer peripheral edge so as to obtain the above function.
It is formed by a processed portion from which unnecessary portions have been removed by heat such as laser processing.

[0005]

However, since the portion of the above processed portion at the boundary with the unnecessary portion is exposed to a high temperature by heat of a laser or the like, there is a problem that the material characteristics of the boundary portion are changed. . For this reason, even if the spring constant and radial stiffness of the leaf spring are calculated by FEM analysis or the like, the calculation does not take into account changes in the material properties, so the characteristics of the actually processed leaf spring are calculated results. And different. As a result, it becomes impossible to drive the movable body such as the piston at a predetermined cycle, and the performance of the refrigerator is reduced, and the vibration reduction effect by the leaf spring is not sufficiently obtained, and the life of the refrigerator is shortened. .

On the other hand, it is possible that a leaf spring having predetermined characteristics may be obtained by repeating the experiment and the like and considering the change in the material characteristics due to heat. However, there is a problem that a great amount of time is required for the development of the refrigerator, and a variation in the material characteristics of each leaf spring is large, so that stable performance cannot be obtained for each refrigerator.

[0007] The present invention has been made in view of the above-mentioned point, and an object of the present invention is to provide a case in which a leaf spring has a processed portion from which unnecessary portions have been removed by heat such as laser processing as described above. By devising the boundary portion of the processed part with the unnecessary part, the characteristics of the leaf spring are made to substantially match the calculation results, preventing the performance and life of the refrigerator from lowering. And to stabilize the performance for each refrigerator.

[0008]

In order to achieve the above object, according to the present invention, a heat-affected portion at a boundary with an unnecessary portion is removed by polishing in a processed portion from which the unnecessary portion has been removed by heat. .

Specifically, according to the first aspect of the present invention, as shown in FIGS. 1 and 2, the movable body (22) and the movable body (2
A leaf spring (31) for elastically supporting 2) reciprocally and immovably in a direction perpendicular to the reciprocating direction of the movable body (22).
And a reciprocating refrigerator in which gas is compressed or expanded by reciprocating motion of the movable body (22).

The leaf spring (31) has a processed portion from which unnecessary portions have been removed by heat, and a heat-affected portion at a boundary between the processed portion and the unnecessary portion is polished and removed. And

As a result, the portion where the material properties change due to heat is polished and removed, so that the material properties of the leaf spring (31) are substantially uniform in any portions, and the properties such as the spring constant and rigidity are calculated. Can be substantially matched. Therefore, the movable body (22) can be driven at a predetermined cycle, and the vibration of the movable body (22) can be reduced. In addition, since the unstable portion of the material characteristics is removed, the variation in the characteristics of each leaf spring (31) can be reliably reduced. Therefore, the performance and life of the refrigerators can be easily prevented from being reduced, and the performance can be stably maintained for each refrigerator.

According to a second aspect of the present invention, in the first aspect of the present invention, it is assumed that an unnecessary portion is removed from the processed portion by laser processing.

That is, the laser processing is performed by a leaf spring (31).
Is easily processed into a predetermined shape, while the high heat easily changes the characteristics of the leaf spring (31) material.
It is particularly difficult to match the characteristics of the leaf spring (31) with the calculation results. Therefore, while facilitating the processing of the leaf spring,
The invention of claim 1 can be effectively used.

According to a third aspect of the present invention, in the second aspect of the present invention, as shown in FIG. 1, the processing portion forms a slit hole (31a) extending between the central portion and the outer peripheral edge portion. Shall be

That is, since the slit hole (31a) has a small slit width, it is optimal to form the slit hole (31a) by laser processing. On the other hand, both ends of the slit hole (31a) in the width direction have characteristics of the leaf spring (31). This is a part that greatly affects, and if the material properties of that part change, the leaf spring (3
The characteristic of 1) is greatly different from the calculation result. Therefore, the invention of claim 1 can be further effectively utilized while facilitating the processing of the slit hole (31a).

According to the fourth aspect of the present invention, the first, second, or third aspect
In the invention of FIG. 1, as shown in FIG.
Has a piston (9) that defines a compression chamber (11) in a cylinder (5) in the compressor (A).

As a result, the radial displacement of the piston (9) of the compressor (A) is a major factor in generating vibration,
Since it is required to minimize the deviation, this leaf spring (31) is optimally used for elastically supporting the movable body (22) constituting the piston (9) of the compressor (A). Become. Therefore, the invention of claim 1, 2 or 3 can be effectively used.

According to the invention of claim 5, according to claim 1, 2 or 3
In the invention of FIG. 1, as shown in FIG.
Has a displacer (40) that partitions and forms an expansion chamber (36) in a cylinder (35) in the expander (B). By doing so, the same operation and effect as the invention of claim 4 can be obtained.

According to a sixth aspect of the present invention, as shown in FIGS. 1 and 2, a movable body (22) for compressing or expanding a gas by reciprocating movement is reciprocally movable and a reciprocating direction of the movable body (22). It is an invention of a leaf spring for a reciprocating refrigerating machine that is elastically supported to be immovable in a direction perpendicular to the vertical direction.

According to the present invention, the leaf spring has a processed portion from which an unnecessary portion is removed by heat, and a heat-affected portion at a boundary between the processed portion and the unnecessary portion is polished and removed. And By doing so, the same operation and effect as the first aspect of the invention can be obtained.

According to a seventh aspect of the present invention, as shown in FIGS. 1 and 2, a movable body (22) for compressing or expanding gas by reciprocating movement is reciprocally movable and a reciprocating direction of the movable body (22). It is an invention of a method of manufacturing a leaf spring for a reciprocating refrigerating machine that is elastically supported so as not to be movable in a direction perpendicular to the vertical direction.

According to the present invention, an unnecessary portion is removed from the leaf spring material by heat to form a processed portion, and a heat-affected portion at a boundary between the processed portion and the unnecessary portion is polished and removed. I do. Thus, the same function and effect as the first aspect of the invention can be obtained.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 schematically shows a Stirling refrigerator as a reciprocating refrigerator according to an embodiment of the present invention. The refrigerator (A) compresses refrigerant gas.
And an expander (B) for expanding the refrigerant gas discharged from the compressor (A).

The compressor (A) has a closed cylindrical casing (1) extending in the left-right direction in the figure. The casing (1) has a cylindrical wall (1a) and the cylindrical wall (1a).
Disk wall portion (1b) for closing the openings at both ends in an airtight manner,
(1b). A cylindrical cylinder (5) having both ends opened and extending in the left-right direction is mounted and fixed concentrically to the cylindrical wall (1a) on the left disk wall (1b) of the casing (1).

A cylindrical piston (9) is slidably fitted in the cylinder (5), and a compression chamber (11) is defined by the piston (9) in the cylinder (5). ing. The compression chamber (11) is provided substantially at the center of the left disk wall (1b) in the casing (1).
A through hole (13) communicating with the through hole (1) is formed.
One end of the connecting pipe (14) is connected to 3).

The piston (9) includes a casing (1)
The piston (9) is drivingly connected to a linear motor (16) as a driving source for reciprocatingly driving the piston (9) in the left-right direction via a support shaft (15) extending in the left-right direction concentrically with the cylindrical wall portion (1a). . That is, the linear motor (16)
Is a cylindrical yoke (17) made of pure iron fixed to the inner peripheral surface of the cylindrical wall (1a) of the casing (1).
An annular permanent magnet (18) is fixed to the outer peripheral side surface in the ring-shaped recess (17a) provided on the right end surface of the yoke (17). The yoke (17) made of iron is used as a yoke to generate a magnetic field of a predetermined strength in the recess (17a).

A bottomed cylindrical bobbin (19) is integrally connected to the right end of the support shaft (15). The cylindrical portion (19a) of the bobbin (19) has the concave portion (17).
It is arranged so as to be able to reciprocate in the left-right direction within a). An electromagnetic coil (20) is wound around the outer peripheral surface of the cylindrical portion (19a) of the bobbin (19) at a position facing the magnet (18). By energizing an alternating current of a predetermined frequency to the electromagnetic coil (20) of the linear motor (16), the piston (9) is reciprocated at a period determined by the spring constants of leaf springs (31) and (31) described later. Thus, a gas pressure of a predetermined cycle is generated in the compression chamber (11).
Thus, the piston (9), the support shaft (15), the bobbin (19), and the electromagnetic coil (20) are connected to the compressor (A)
This constitutes a movable body (22) of the compressor (A) which reciprocates integrally in the left and right directions.

At the left and right ends of the support shaft (15), that is, at two places separated in the left and right direction with the linear motor (16) interposed therebetween, a pair of disc-shaped leaf springs (31),
(31) is fixedly arranged. Each leaf spring (31)
Is fixed to the inner peripheral surface of the cylindrical wall portion (1a) of the casing (1) at the outer peripheral portion. Each of the leaf springs (31) is formed by laminating two thin plates.
As shown in FIG. 3, three substantially spiral slit holes (31a) extending between the central portion and the outer peripheral edge portion are provided.
Are formed at substantially equal intervals in the circumferential direction. With this,
Each of the leaf springs (31) has high radial rigidity and hardly deforms in that direction, while deformation of the respective leaf springs (31) in the central axis direction at the central portion thereof. The movable body (22) is elastically supported so as to be able to reciprocate in a substantially horizontal direction and immovable in a direction perpendicular to the reciprocating direction of the movable body (22). .

Each slit hole (3) of each leaf spring (31)
1a) is formed by a processed portion from which unnecessary portions have been removed by laser processing (by heat of a laser). Then, a heat-affected portion at the boundary between the processed portion and the unnecessary portion, that is, both ends in the width direction of each slit hole (31a) (a range of several hundred μm from both end surfaces in the width direction of each slit hole (31a)).
Has been polished and removed, so that the portions where the material properties have changed due to the heat of the laser have been completely removed. still,
Both ends in the length direction of each slit hole (31a) are formed in a circular shape in order to reduce stress concentration.
In addition, in FIG. 1, (31b) is a through hole for fitting and fixing to the support shaft (15).

On the other hand, the expander (B) has a cylindrical cylinder (35). Inside the cylinder (35), the space inside the cylinder (35) is defined by an expansion chamber (36) and a working chamber (3).
7), a displacer (40) is formed so as to reciprocate in the left-right direction. This displacer (40) is filled with a metal regenerator (regenerative heat exchanger), and the space filled with the regenerator is:
The expansion chamber (36) and the working chamber (37) communicate with each other. When the low-temperature refrigerant gas expanded in the expansion chamber (36) goes to the working chamber (37), the refrigerant gas cools the cold storage material to store cold heat in the cold storage material. When going from the working chamber (37) to the expansion chamber (36), the refrigerant gas is cooled by the cold storage material.

In the vicinity of the base end of the cylinder (35),
A through hole (43) communicating with the working chamber (37) is formed, and the other end of the coupling pipe (14) is connected to the through hole (43). This allows the working chamber (37)
Is connected to the compression chamber (11) of the compressor (A) via the coupling pipe (14), and the refrigerant gas expands by reciprocating the displacer (40) by the refrigerant gas pressure from the compressor (A). By expanding in the chamber (36), cold is generated in the cold head (44) at the tip of the cylinder (35).

At the base end of the cylinder (35), like the casing (1) of the compressor (A), a cylindrical wall (5) is provided.
1a) and a closed cylindrical casing (51) extending in the left-right direction and including two disk wall portions (51b) and (51b).
Is attached and fixed. In the casing (51), a support shaft (55) integrally fixed to the displacer (40) is provided so as to extend in the left-right direction concentrically with the cylindrical wall portion (51a). That is, the displacer (40) and the support shaft (55) constitute a movable body (22) of the expander (B) that reciprocates left and right integrally in the expander (B). The support shaft (55) penetrates the left disk wall (51b) of the casing (51), and a seal member (55) of the disk wall (51b) penetrates the support shaft (55). 57)
The sealing member (57) seals the refrigerant from the working chamber (37) so as not to leak into the casing (51).

As in the case of the movable body (22) of the compressor (A), a pair of leaf springs (31) are provided at two positions on the support shaft (55) in the casing (51) that are separated in the left-right direction. , (31) are fixedly arranged.
According to 1), the movable body (22) of the expander (B) is elastically supported so as to be able to reciprocate in a substantially horizontal direction and immovable in a direction perpendicular to the reciprocating direction of the movable body (22).

The operation of the above-structured Stirling refrigerator will be described. First, with the start of the operation of the refrigerator, an AC power supply having a predetermined frequency is supplied to the electromagnetic coil (20) of the linear motor (16) in the compressor (A).
With this energization, the movable body (22) of the compressor (A) deforms the center of each leaf spring (31) of the compressor (A) in the left-right direction by the action of the magnetic field generated by the magnet (18). While the piston (9) reciprocates from the neutral position, the volume of the compression chamber (11) increases or decreases due to the reciprocation of the piston (9), and a pressure wave of a predetermined cycle is generated in the compression chamber (11). Since the compression chamber (11) communicates with the expander (B) via the coupling pipe (14), when the pressure in the compression chamber (11) increases, the pressurized refrigerant gas is supplied to the working chamber ( 37) to increase the pressure in the working chamber (37). This increase in pressure causes a difference between the working chamber (37) and the expansion chamber (36). The pressure difference causes the displacer (40) to move the center of each leaf spring (31) of the expander (B) to the left. The cylinder (35) moves to the tip side while being deformed. Since the working chamber (37) communicates with the expansion chamber (36) via the space in the displacer (40), in the next stage, the gas in the working chamber (37) passes through the displacer (40) and cools. Flows into the expansion chamber (36) while being cooled by the material,
The differential pressure between the two chambers (36) and (37) disappears, and the displacer (40) moves to the base end side of the cylinder (35) by the restoring force of each leaf spring (31) of the expander (B) and returns to its original position. Return to

Thereafter, immediately, the piston (9) of the compressor (A) retreats and the pressure in the compression chamber (11) decreases. Therefore, the refrigerant gas in the working chamber (37) is connected to the connecting pipe (1).
Returning to the compression chamber (11) via 4), the pressure in the working chamber (37) becomes lower than that in the expansion chamber (36). Due to the pressure difference between the working chamber (37) and the expansion chamber (36), the displacer (40) in turn causes each leaf spring (3) of the expander (B) to move.
Cylinder (35) while deforming the center of 1) to the right
The refrigerant gas moves to the proximal end side, and adiabatic expansion of the refrigerant gas in the expansion chamber (36) occurs, thereby causing cold. In the next stage, the expanded gas flows from the expansion chamber (36) through the displacer (40) to the working chamber (37) while applying cold heat to the regenerator material.
6), the differential pressure of (37) disappears and the displacer (4)
0) moves to the tip side of the cylinder (35) by the restoring force of each leaf spring (31) of the expander (B) and returns to the original position. One cycle is completed as described above, and thereafter, by repeating the same cycle, the cold head (44) at the tip of the cylinder (35) is gradually cooled to the cryogenic temperature.

In this embodiment, each slit hole (31a) of each leaf spring (31) for elastically supporting each movable body (22) of the compressor (A) and the expander (B) has unnecessary portions by laser processing. Since it is formed by the processed portion removed, it can be easily formed even if its slit width is small. At this time, the material characteristics of both ends in the width direction of each slit hole (31a), which is a heat-affected portion at the boundary between the processed portion and the unnecessary portion, change due to the high heat of the laser. Since this portion greatly affects the characteristics of each leaf spring (31), if the material characteristics of that portion change, the characteristics of the leaf spring (31) will greatly differ from the calculation results obtained by FEM analysis or the like. .

However, in this embodiment, since the heat-affected portion is polished and removed, the portion in which the material characteristics have changed is removed, and the material characteristics of each leaf spring (31) are substantially uniform in any portion. Thus, the characteristics such as the spring constant and the rigidity of each leaf spring (31) can be made substantially coincident with the results calculated in consideration of the amount to be polished and removed in advance. As a result, each movable body (22) can be driven at a predetermined cycle, and the vibration of each movable body (22) can be reliably reduced. In addition, since the unstable portion of the material characteristics is removed, the variation in the characteristics of each leaf spring (31) can be surely suppressed. Therefore, the performance and the life of the refrigerator can be prevented from being reduced by a simple method, and stable performance can be obtained for each refrigerator.

In the above embodiment, each leaf spring (31)
Each slit hole (31a) is formed by a processed portion from which unnecessary portions have been removed by laser processing. However, a processing in which unnecessary portions have been removed by laser processing on a central through-hole (31b) and an outer peripheral portion. It may be formed by a part. Also in this case, the heat-affected portion at the boundary between the processed portion and the unnecessary portion may be polished and removed. In addition, any processing other than laser processing may be used as long as the processing removes unnecessary portions using heat.

Further, in the above embodiment, each leaf spring (3
Although 1) was composed of two thin plates, the number of thin plates may be any number, and the number of thin plates and the thickness of the compressor (A) and the expander (B) may be different from each other.

[0040]

As described above, according to the first aspect of the present invention, the movable body is provided with a leaf spring that elastically supports the movable body so that the movable body can reciprocate and cannot move in the direction perpendicular to the reciprocating direction of the movable body. In contrast to a reciprocating refrigerator in which gas is compressed or expanded by reciprocation of the body, the above-mentioned leaf spring has a processed portion in which an unnecessary portion is removed by heat, and an unnecessary portion of the processed portion. The heat-affected zone at the boundary between the two was polished and removed. According to the sixth aspect of the present invention, there is no need for heat for the reciprocating refrigerator leaf spring which elastically supports the movable body so as to be capable of reciprocating and immovable in a direction perpendicular to the reciprocating direction of the movable body. The heat-affected portion at the boundary between the processed portion and the unnecessary portion is removed by polishing. Further, according to the invention of claim 7, as a method of manufacturing a leaf spring for a reciprocating refrigerator, an unnecessary portion is removed from a leaf spring material by heat to form a processed portion, and a boundary between the processed portion and the unnecessary portion is formed. Was removed by polishing. Therefore, according to these inventions, it is possible to easily prevent the performance and life of the refrigerator from being reduced, and to stabilize the performance of each refrigerator.

According to the second aspect of the present invention, the processed portion is formed by removing unnecessary portions by laser processing.
The invention of claim 1 can be effectively used while facilitating the processing of the leaf spring.

According to the third aspect of the present invention, the processing portion forms the slit hole extending between the central portion and the outer peripheral edge portion, so that the processing of the slit hole is facilitated while the processing of the slit hole is facilitated. Further effective use of the invention can be achieved.

According to the fourth aspect of the present invention, the movable body has a piston which defines a compression chamber in a cylinder in the compressor. Further, in the invention according to claim 5, the movable body has a displacer that defines an expansion chamber in a cylinder in the expander. Therefore, according to these inventions, the invention of claims 1, 2 or 3 can be effectively used.

[Brief description of the drawings]

FIG. 1 is a plan view showing a leaf spring.

FIG. 2 is a schematic cross-sectional view illustrating an entire configuration of a Stirling refrigerator as a reciprocating refrigerator according to the first embodiment of the present invention.

[Explanation of symbols]

 (A) compressor (B) expander (9) piston (11) compression chamber (22) movable body (31) leaf spring (31a) slit hole (36) expansion chamber (40) displacer

Claims (7)

[Claims] 1. A movable body (22) and a leaf spring (31) for elastically supporting the movable body (22) so as to be reciprocally movable and immovable in a direction perpendicular to the reciprocating direction of the movable body (22). A reciprocating refrigerating machine that compresses or expands gas by reciprocating motion of a movable body (22), wherein the leaf spring (31) removes a processed part from which unnecessary parts have been removed by heat. A reciprocating refrigerating machine, wherein a heat-affected portion at a boundary between the processed portion and an unnecessary portion is removed by polishing. 2. The reciprocating refrigerating machine according to claim 1, wherein the processing portion has an unnecessary portion removed by laser processing. 3. The reciprocating refrigerating machine according to claim 2, wherein the processing portion has a slit hole (31a) extending between the central portion and the outer peripheral edge portion. Dynamic refrigerator. 4. A reciprocating refrigerating machine according to claim 1, wherein the movable body (22) defines a compression chamber (11) in a cylinder (5) of the compressor (A). A reciprocating refrigerating machine having (9). 5. The reciprocating refrigerating machine according to claim 1, wherein the movable body (22) is a cylinder (3) in the expander (B).
5) A reciprocating refrigerator having a displacer (40) for forming an expansion chamber (36) therein. 6. A reciprocating refrigeration system that reciprocates a movable body (22) for compressing or expanding gas by reciprocating motion and resiliently supports the movable body (22) immovably in a direction perpendicular to the reciprocating direction of the movable body (22). A machine leaf spring, comprising: a processed portion from which an unnecessary portion is removed by heat, wherein a heat-affected portion at a boundary between the processed portion and the unnecessary portion is polished and removed. Leaf spring for dynamic refrigerator. 7. A reciprocating refrigeration system that reciprocates a movable body (22) for compressing or expanding gas by reciprocating motion and resiliently supports the movable body (22) immovably in a direction perpendicular to the reciprocating direction of the movable body (22). A method for manufacturing a leaf spring for a machine, comprising: removing an unnecessary portion from a leaf spring material by heat to form a processed portion; and polishing and removing a heat-affected portion at a boundary between the processed portion and the unnecessary portion. A method for manufacturing a leaf spring for a reciprocating refrigerating machine.